NEW YORK (Reuters) - The U.S. Trade Representative has upheld an import ban on Arista Networks Inc's ethernet switches following a federal commission's finding in June that the company's products infringed patents owned by rival Cisco Systems Inc, Cisco said.

The decision by the U.S. International Trade Commission (ITC), which investigates purported violations of U.S. intellectual property, stemmed from a complaint Cisco filed in December 2014 about the switches, which are used in computer data centers and servers.

In a blog post on the company's website on Monday, Cisco general counsel Mark Chandler said the import ban was to start on Tuesday. Representatives for the USTR could not immediately be reached for comment on Tuesday.

The ITC said Arista infringed three Cisco patents relating to managing and securing communications networks. The ruling excludes the import of Arista's network devices, including its 7000 series of switches, which generates most of that company's product revenue, according to regulatory filings. It also prevents the sale of domestic supplies of the imported products.

In a statement on Tuesday, Arista's general counsel, Marc Taxay, said the company has redesigned the software in its switches and believes it is in "full compliance" with the ITC's orders.

"Our primary focus remains the continued supply of non-infringing products to our customers," he said.

Arista also said it would appeal to the U.S. Court of Appeals for the Federal Circuit.

Cisco's Chandler, in his blog post, said that "it appears Cisco's proprietary technology is still being used."

He said Arista has not received approval from the ITC for the redesigned products.

The case is In the Matter of Certain Network Devices, 337-944, at the U.S. International Trade Commission.